Comment 2 for bug 2015364

Not only skip level jobs but also normal ovn grenade multinode jobs are also impacted[1]. Basically any multinode job running kernel>=5.5 and deploying ovs/ovn from source will be impacted.

The issue got visible after grenade jobs switched to jammy[2]. Since jammy have kernel >=5.5 openvswitch modules doesn't get's reloaded(already loaded as part of multi-node-bridge execution) after ovs is installed from source[3]. And until it get's reloaded the traffic to/from ovs ports do not work.

So we need to reload the modules always irrespective of build_modules is True or False. Also build modules is deprecated since OVS2.15 and dropped with OVS3.0[4]. This can additionally handled as seperate patch.

As it's part of devstack install reloading modules always shouldn't hurt as we need not worry about dataplane downtime. Will push a patch to devstack(as [3] now lives there) and backport to stable branches in order to fix it. Verified in [5].

[1] https://zuul.openstack.org/builds?job_name=neutron-ovn-grenade-multinode
[2] https://review.opendev.org/c/openstack/grenade/+/877998
[3] https://review.opendev.org/c/openstack/neutron/+/726759
[4] https://github.com/openvswitch/ovs/commit/422e90437
[5] https://review.opendev.org/c/openstack/neutron/+/878761